1. Field of the Invention
The present invention relates to an apparatus and method for measuring the ride height of a vehicle. More particularly, the invention relates to an apparatus and method for taking indirect measurements of vehicle body elevation relative to the suspension system.
2. Description of Related Art
The ride height of a vehicle is generally considered to be the elevation of the vehicle body with respect to the vehicle suspension system. Vehicle wheel alignment is closely related to ride height in that, over time, changes in the suspension system due to worn or damaged springs, shocks, ball joints or the like can affect wheel alignment. Since manufacturers' specifications for wheel alignment factors such as camber and toe are typically provided with respect to a new suspension system, it is important that changes in the suspension system be accounted for before performing a wheel alignment. These changes can be measured by comparing the values for the ride height of a new vehicle, which are typically provided by the manufacturer, with the actual measured values for ride height.
In the prior art, ride height is measured by determining the vertical distances between points on the vehicle and the ground, e.g., between the rocker panel and the ground, and/or between two points on the suspension system, e.g., between the rear inner bushing bolt and the rear outer bushing bolt. These distances are typically measured by a service technician using a tape measure. However, certain devices and methods have been developed to make these measurements easier. For example, U.S. Pat. No. 4,977,524 to Strege et al. discloses an apparatus for visually displaying representations of the appropriate measuring points for a specific vehicle and an electronic measuring gauge for automatically transmitting the values measured by the technician at these points to a system computer. The main drawback with many prior art devices, however, is that the vertical measurements must be taken directly, but the configuration of the suspension system often interferes with such direct vertical measurements. As a result, the service technician often approximates the measurements and this can lead to inaccurate ride height determinations.